Synthesis and characterization of α-Fe2O3/polyaniline nanotube composite as electrochemical sensor for uric acid detection

We report the synthesis of alpha-Fe2O3/polyaniline nanotube (PAn NTs) composite as an electrochemical sensor for uric acid (UA) detection. Field emission scanning electron microscopy (FESEM) indicates a hexagonal shape of the alpha-Fe2O3 while a nanotube morphology of the PAn. Impedance spectroscopy results confirm a significant decrease in the charge transfer resistance of the glassy carbon electrode (GCE) modified with alpha-Fe2O3/PAn NTs due to the presence of PAn NTs. The results show that the increase in the conductivity of alpha-Fe2O3 in the presence of PAnNTs could improve the catalytic performance of alpha-Fe2O3/PAn NTs composite, compared to the pure alpha-Fe2O3 nanoparticles. From differential pulse voltammetry, a linear working range for the concentration of UA between 0.01 mu M and 5 mu M, with a LOD of 0.038 mu M (S/N = 3) was obtained. The sensitivity of the linear segment is 0.433 mu A mu M-1. The reliability of the modified electrode towards the detection of UA was investigated in the presence of interfering acids such as ascorbic acid, citric acid and succinic acid. (C) 2018 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.